import os

# 根据环境变量动态选择配置类
def Config():
    if os.environ.get('APP_ENV') == 'production':
        from .production import ProductionConfig as DefaultConfig
    elif os.environ.get('APP_ENV') == 'testing':
        from .testing import TestingConfig as DefaultConfig
    else:
        from .development import DevelopmentConfig as DefaultConfig
    return DefaultConfig